textproduct: Albany

WHAT HAS CHANGED

Winter Storm Watch has been upgraded to a Winter Storm Warning in northern Herkimer and Hamilton Counties for heavy snowfall, with a Winter Weather Advisory issued for northern Fulton and northern Warren Counties in NY and the southern Green Mountains for moderate snowfall Friday afternoon into Saturday afternoon.

Flood Watch has been canceled, since no new or additional flooding is anticipated. Flooding Warnings continue for minor flooding along the Housatonic River.

Wind Advisory has been canceled, with gusts around 30 to 40 mph expected through the rest of the afternoon.

KEY MESSAGES

1) Minor river flooding is occurring along the Housatonic River in NW CT, today into Friday due to the runoff from snow melt and rainfall.

2) A period of snow showers expected this afternoon for some areas south and east of Albany, with less than one inch of snow accumulation across portions of the Taconics, Berkshires and Litchfield Hills.

3) Clipper system brings moderate to locally heavy snowfall across portions of SW Adirondacks and southern Green Mountains Friday afternoon into early Saturday afternoon. Strong gusty winds also expected associated with, and behind this clipper system late Friday night into Saturday.

4) Another storm system approaching from the west could bring another round of strong winds and locally heavy rainfall Sunday night through Monday night.

DISCUSSION

KEY MESSAGE 1...

Minor flooding continues to occur along the Housatonic River at Falls Village, Gaylordsville and below Stevenson Dam, where Flood Warnings remain in effect. Otherwise, most river levels will generally crest today into tonight. The Flood Watch has been cancelled since no additional rainfall is expected to contribute to runoff.

KEY MESSAGE 2...

An upper level trough moving eastward this afternoon into early this evening looks to interact with moisture trailing behind the old cold front. Once low level temperatures cool down enough, a period of light snow is still likely to result, with some minor accumulations for some areas south/east of Albany especially Taconics, Berkshires and Litchfield Hills where less than an inch of wet snow may accumulate. This could cause slippery travel on untreated roads in this area later this afternoon into this evening.

KEY MESSAGE 3...

A strong clipper system approaching from the upper Great Lakes will bring an initial period of snow associated with isentropic lift Fri afternoon, with the primary surface cyclone centered well to our north/west. With strengthening S-SW flow aloft, the snow will be strongly modulated by the wind with upslope flow enhancing snow into the S. Adirondacks, with downsloping across the Greater Capital District. Also, due to the expected cyclone track across Lake Ontario, far N. NY and eventually N. New England, the best forcing will also be over W. and S. Adirondacks. Consistent model QPF resulting in 5-11" snow in N. Herkimer/Hamilton counties, where the Winter Storm Watch has been upgraded to a Winter Storm Warning. Will also issue a Winter Weather Advisory for 3-7" of snow in N. Fulton and N. Warren County and in the S. Greens of VT above 1500 ft. Accumulations elsewhere should be minor around 1-3" and not result in any headlines. Even though temperatures should rise well into the 30s in valleys, wetbulb effect should quickly turn any rain to snow during periods of steady precip. As the cyclone tracks east of our area by early Sat, the flow shifts to the west with additional upslope enhancement into the W. Adirondacks and S. Greens.

Strong/gusty winds are also anticipated with the clipper system. S-SW flow ahead of the cyclone could gust 25-35 mph in favored spots Fri into Fri night. However, the W-NW flow on Sat could result in gusts of 35-50 mph due to cold advection resulting more widespread deeper mixing along with a significant pressure gradient. Latest 24-hr NBM probs ending 2 AM Sun for wind gusts > 45 mph are 50-80% across parts of the Mohawk Valley, Capital District, N/ Taconics, Berkshires, SE Adirondacks and E. Catskills. Wind Advisories may eventually be needed for these areas.

KEY MESSAGE 4...

The active pattern looks to continue, with another storm system approaching from the Great Lakes and Midwest expected to bring potentially strong winds and locally heavy rainfall Sun night through Mon night. After a cool weekend, the pattern amplifies with flat ridging along the east coast and a strong southerly flow developing Sun night into Mon, as the primary cyclone tracks NE through the central Great Lakes. So southerly winds could become strong especially in favored S-N channeling areas and south-facing mountain slopes. Temperatures will also warm to above normal levels on Mon, which will lead to some additional snowmelt in the S. Adirondacks and S. Greens. The system's cold front could focus a narrow ribbon of anomalous moisture, which could lead to a period of heavy rain in the Mon afternoon or evening period. PWAT anomalies are forecast to be around +2 to +3 STDEV from the NAEFS. Runoff from rainfall and snowmelt could lead to some river flooding. Strong winds may also occur on in wake of the cold front in the developing westerly flow regime Mon night into Tue.

AVIATION /18Z THURSDAY THROUGH TUESDAY/

Through 18z Friday...VFR conditions prevail across all terminals this afternoon with lower-level moisture having been scoured out by fairly deep mixing. For some, ALB and PSF, ceiling heights err on the lower bound of VFR thresholds, though according to latest forecast soundings, ALB should be continuing to improve through the afternoon. PSF may have a bit of a different story as some lingering light precipitation and upslope flow could see a varying of ceiling heights between low VFR and high MVFR into late this evening.

Once the boundary to our south shifts farther away from our region tonight, high pressure briefly builds in and will continue to erode any lasting ceilings. Therefore, once PSF improves, VFR conditions will be in place everywhere for the remaining of the TAF period beginning late this evening. However, beginning within the last few hours of the 18z TAF period, clouds will be on the increase in advance of a clipper system that will be approaching the region and bringing precipitation again for late Friday.

Winds will remain gusty out of the northwest through this afternoon and into this evening before gradually decreasing throughout the overnight tonight and shifting to the southwest by tomorrow morning. Sustained speeds this afternoon will peak between 10-20 kt with gusts ranging from 20-35 kt particularly at ALB and PSF. Overnight, sustained speeds will fall largely below or up to 10 kt.

Outlook...

Friday Night: Moderate Operational Impact. Breezy. Chance of RA...SN. Saturday: Moderate Operational Impact. Windy With Gusts To 37 kts. NO SIG WX. Saturday Night: Moderate Operational Impact. Windy With Gusts To 30 kts. NO SIG WX. Sunday: Moderate Operational Impact. Breezy. Chance of SN. Sunday Night: High Operational Impact. Breezy. Likely RA. Monday: High Operational Impact. Windy With Gusts To 30 kts. Definite RA. Monday Night: High Operational Impact. Breezy. Definite RA...SN. Tuesday: Low Operational Impact. Breezy. NO SIG WX.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...Winter Storm Warning from 11 AM Friday to 2 PM EDT Saturday for NYZ032-033. Winter Weather Advisory from noon Friday to 2 PM EDT Saturday for NYZ042-082. MA...None. VT...Winter Weather Advisory from noon Friday to 2 PM EDT Saturday for VTZ013-014.